[13.3] nutrient cycles (2/2) the phosphorus cycle Flashcards
1
Q
what do we need phosphorous for?
A
- phospholipids
- ATP
- nucleic acids
- NAD
- NADP
- FAD
- acetyl CoA
2
Q
what form of phosphate do organisms usually use?
A
phosphate ion form
3
Q
describe the phosphorus cycle
A
- dissolved phosphate ions in oceans, lakes, and soils ➞ phosphate ions in plants via absorption
- dissolved phosphate ions ➞ phosphates in rocks via sedimentation
- phosphate ions in plants ➞ phosphate ions in animals via feeding and digestion
- phosphate ions in animals ➞ phosphate ions in wastes and remains eg. guano, bones and shells via excretion and decomposition
- phosphate ions in animals ➞ dissolved phosphate ions in oceans, lakes, and soils via excretion
- phosphate ions in waste and remains ➞ dissolved phosphate ions in oceans, lakes, and soils via erosion
- phosphate ions in wastes and remains ➞ phosphates in rocks via deposition
- phosphates in rocks ➞ dissolved phosphate ions in oceans, lakes, and soils via erosion and use of fertilisers
4
Q
describe the role of microorganisms in the phosphorus cycle (2)
A
- function as decomposers / saprobionts
- that break down the molecules in dead organisms to release phosphate ions into the ground
5
Q
what problems can arise when fertilisers run in waterways?
A
- eutrophication
- algal blooms which lead to low-oxygen waters that can kill fish and reduce essential fish habitats
- when the excessive algae decomposes, a large amount of carbon dioxide is produced, which lowers the pH of seawater